Milky Way could be catapulting stars into its outer halo
Eleanor Imster in SPACE | May 3, 2020

Scientists used computer simulations to learn that our Milky Way galaxy may sometimes launch newly forming stars into the space around itself – that is, into the halo of our galaxy – via outflows triggered by supernova explosions.


An example of one of the movies from the FIRE-2 simulations

Though mighty, the Milky Way and galaxies of similar mass are not without scars chronicling turbulent histories.

So say scientists at the University of California, Irvine, who used the “hyper-realistic, cosmologically self-consistent” computer simulations generated via the FIRE-2 collaboration (FIRE stands for Feedback in Realistic Environments) to model our Milky Way galaxy’s rotation over time. In this way, they’ve learned that our galaxy may sometimes launch newly forming stars into the space around itself – that is, into the halo of our galaxy – via outflows triggered by supernova explosions.

UC Irvine physicist Sijie Yu is lead author of this new study, which was published in March, 2020 in the peer-reviewed Monthly Notices of the Royal Astronomical Society. Yu said the findings were made possible partly by the availability of a powerful new set of computing tools. She said in a statement:

The FIRE-2 simulations allow us to generate movies that make it seem as though you’re observing a real galaxy.

They show us that as the galaxy center is rotating, a bubble driven by supernova[s] is developing, with stars forming at its edge. It looks as though the stars are being kicked out from the center.